Slider for a plastic bag

ABSTRACT

A slider ( 10 ) to be positioned in straddling relationship on a reclosable fastener means for a bag formed by a pair of plastic sheets having separable fastener means extending along an opening for the bag and including reclosable interlocking rib and groove profiles along the plastic sheets at said opening of the bag. The slider includes a support member ( 11 ), in use, overlying the opening to the bag and straddling the fastening means, and also carrying a separating finger ( 12 ) adapted, in use, to engage within and adapted to separate the fastening means when the slider is moved in one direction, and a pair of legs ( 13 ) depending therefrom to force the fastener means into interlocking relationship when the slider is moved in the opposite direction along the fastening means. A pair of foldable sidewalls or wings ( 15 ) are integrally hinged at ( 16 ) to a side edge of each of the legs and foldable relative to their associated leg, and means are provided to interlock the sidewalls with their associated legs, whilst ledges ( 20 ) on the foldable sidewalls or wings retain the slider on the bag and beneath the fastening means to prevent the slider from being laterally removed from beneath the fastening means.

TECHNICAL FIELD

[0001] This invention relates to improvements in plastic sliders for opening and closing reclosable fasteners on plastic bags and the like, and more particularly a foldable, preferably plastic, slider which straddles a profiled plastic reclosable fastener, and particularly suited for thermoplastic bags and the like formed by a pair of flexible plastic sheets having top edges with separable fastening means extending along the lengths of the top edges and therefore at the opening of the bag.

BACKGROUND ART

[0002] The separatable fastener means comprises reclosable interlocking rib and groove profiled formations on the respective sheets. Such sliders conventionally have a separator finger carried by a complimentary structure which has a transverse finger support member from which legs depend as well as foldable side walls or wings. Means are provided to interlock the side walls or wings to the legs whereby to attach the slider to the bag and around the fastener, with the finger serving to separate the fastener as the slider is moved in one direction along the separable fastener means, whilst the legs of the slider press the rib and groove of the fastener means together to close the fastener when the slider is moved in the opposite direction.

[0003] Such a slider is disclosed in published U.S. Pat. No. 5,010,627 and various improvements therein have been disclosed in subsequently published U.S. Pat. Nos. 5,063,644, 5,070,583 and 5,867,875.

[0004] However, such known sliders are subject to some problems in relation not only to the complexity of their manufacture as a one piece structure, but which is not a major problem, but more particularly in the complexity of manufacturing the bag and slider combination insofar as attachment of the slider to the bag during manufacture is concerned. With the known sliders they have been associated with the fasteners of the bag by a combination of movements, involving at least swinging the sidewalls or wings downwardly once the slider has been positioned over the opening of the bag and around the fastener means.

DISCLOSURE OF THE INVENTION

[0005] It is therefore an object of the present invention to minimise the above problems of associating the slider with the fastening means during manufacture of the bag, and more particularly a slider which lends itself to association by manually, or by machine, sliding the slider longitudinally onto one end of the fastener means and subsequently also manually, or by machine, folding the sidewalls or wings longitudinally of the fastener means. This does not rule out the possibility the slider may be firstly moved manually, or by machine, laterally (for example vertically downwardly) over the fastener means and then manually, or by machine, subsequently closing the foldable sidewalls or wings.

[0006] In accordance with the present invention there is envisaged, a slider to be positioned in straddling relationship on a reclosable fastener means for a bag formed by a pair of plastic sheets having separable fastener means extending along an opening for the bag and including reclosable interlocking rib and groove profiles along the plastic sheets at said opening of the bag, wherein the slider includes a support member, in use, overlying the opening to the bag and straddling said fastening means, and also carrying a separating finger adapted, in use, to engage within and adapted to separate said fastening means when the slider is moved in one direction, and a pair of legs depending therefrom to force said fastener means into interlocking relationship when the slider is moved in the opposite direction along said fastening means, and wherein means are provided to retain said slider on said bag and beneath said fastening means to prevent said slider from being laterally removed from beneath said fastening means.

[0007] Preferably said slider also has at least one foldable sidewall or wing integrally hinged to a side edge of at least one leg and foldable relative to its associated leg, and means are provided to interlock said sidewall with its associated leg.

[0008] Preferably the means to retain said slider on said bag is part of the, or each, said hinged sidewall.

[0009] Preferably each said leg of the slider has a foldable sidewall associated therewith.

[0010] Preferably each said sidewall carries the means to retain said slider on said bag and around said fastener means.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] One preferred embodiment of the invention will now be described with reference to the accompanying drawings, in which;

[0012]FIG. 1 is a perspective view of the slider in the closed position relative to a plastic bag,

[0013]FIG. 2 is a similar perspective view of the slider prior to being closed around the fastening means of the plastic bag, and

[0014]FIG. 3 is a more detailed perspective view of the slider of this preferred embodiment of the invention.

BEST MODE FOR CARRYING OUT THE INVENTION

[0015] In accordance with this preferred embodiment of the invention reference should be made to the aforementioned prior art US patent publications in relation to the possible forms of fastener means, for closing the opening to the plastic bag.

[0016] The slider of this preferred embodiment is moulded as a one piece plastic component and this is accomplished because the foldable/pivotable sidewalls are moulded integrally with the rest of the slider. Alternatively the slider could be made from a plurality of separate parts which are clipped together.

[0017] The slider, generally indicated as 10, of this preferred embodiment of the invention includes a support member 11 to the underside of which is moulded a separating finger 12 as shown separately from the remainder of the slider in FIG. 3, and may be of any of the configurations shown in the aforementioned prior art US publications, and which would normally be moulded with the remainder of the slider. The support member on opposite side edges thereof has depending legs or panels 13 extending along the opposite longitudinal sides respectively with a pair lugs 14 extending from end thereof. The opposite ends of the legs or panels 13 carry respective foldable sidewalls or wings 15 hinged by integrally moulded hinges 16 to those ends of the legs or panels 13, and have concave formation 17 formed on the outer sides thereof with a multiplicity of ribs as shown to assist in finger gripping during movement of the slider during opening and closing the fastener means of the plastic bags.

[0018] The foldable sidewalls have laterally extending vertical walls 18 and longitudinal walls 19, the longitudinal walls 19 are provided with ledges 20 which underlie the fastener means of the plastic bag to prevent or minimise the movement of the slider from around the fastener means of the plastic bag when the slider is attached to the bag and when the sidewalls or wings are swung to a position against the remainder of the slider as shown in FIG. 1.

[0019] In order to hold the sidewalls or wings 15 in position alongside the legs or panels 13 when the sidewalls or wings are swung to the closed position, the laterally extending edges 18 of the sidewalls incorporate grooves 21 approximating the size of the lugs 14 on the legs or panels 13 and ribs 22 on the insides of the formations defining the sides of the grooves such that when the lugs 14 are received within the grooves 21 the ribs engage on the sides of the legs or panels 13 to hold the sidewalls or wings in position with the ledges 20 of the sidewalls or wings preventing lateral movement of the slider off the fastener means after the slider is in position.

[0020] In order, during manufacture, to attach the slider to an associated plastic bag, the slider is firstly moved either manually, or by a machine, longitudinally onto the fastener means of the plastic bag, or laterally over the fastener means, whereafter the sidewalls or wings are swung into position either manually or by separate mechanical means, and longitudinally of the fastener means. Alternatively the slider may be moved manually or by mechanical means longitudinally onto one end of the fastener means and thereafter the pivotable sidewalls or wings are closed to encapsulate the fastener means within the slider. 

1. A slider to be positioned in straddling relationship on a reclosable fastener means for a bag formed by a pair of plastic sheets having separable fastener means extending along an opening for the bag and including reclosable interlocking rib and groove profiles along the plastic sheets at said opening of the bag, wherein the slider includes a support member, in use, overlying the opening to the bag and straddling said fastening means, and also carrying a separating finger adapted, in use, to engage within and adapted to separate said fastening means when the slider is moved in one direction, and a pair of legs depending therefrom to force said fastener means into interlocking relationship when the slider is moved in the opposite direction along said fastening means, and wherein means are provided to retain said slider on said bag and beneath said fastening means to prevent said slider from being laterally removed from beneath said fastening means.
 2. A slider as claimed in claim 1, wherein said slider also has at least one foldable sidewall or wing integrally hinged to a side edge of at least one leg and foldable relative to its associated leg, and means are provided to interlock said sidewall with its associated leg.
 3. A slider as claimed in claim 1 or 2, wherein the means to retain said slider on said bag is part of the, or each, said hinged sidewall.
 4. A slider as claimed in claim 2 or 3, wherein each said leg of the slider has a foldable sidewall associated therewith.
 5. A slider as claimed in claim 3, wherein each said sidewall carries the means to retain said slider on said bag and around said fastener means.
 6. A slider for opening and closing reclosable fasteners on plastic bags, substantially as hereinbefore described with reference to the accompanying drawings. 